Benzene in soft drinks

Benzene in soft drinks is of potential concern due to the carcinogenic nature of the benzene molecule. This contamination is a public health concern and has caused significant outcry among environmental and health advocates. Benzene levels are regulated in drinking water nationally and internationally, and in bottled water in the United States, but only informally in soft drinks. The benzene forms from decarboxylation of the preservativebenzoic acid in the presence of ascorbic acid (vitamin C) and metal ions (iron and copper) that act as catalysts, especially under heat and light.

Benzene in soft drinks has to be seen in the context of other environmental exposure. Taking the worst example found to date of a soft drink containing 87.9 ppb benzene,[4] someone drinking a 350 ml (12 oz) can would ingest 31 μg (micrograms) of benzene, almost equivalent to the benzene inhaled by a motorist refilling a fuel tank for three minutes. While there are alternatives to using sodium benzoate as a preservative, the casual consumption of such a drink is unlikely to pose a significant health hazard to a particular individual (see, for example, the EPA IRIS document on benzene[7]).

The UK Food Standards Agency has stated that people would need to drink at least 20 litres (5.5 gal) per day of a drink containing benzene at 10 μg to equal the amount of benzene they would breathe from city air every day.[8] Daily personal exposure to benzene is determined by adding exposure from all sources.

Air: A European study found that people breathe in 220 μg of benzene every day due to general atmospheric pollution. A motorist refilling a fuel tank for three minutes would inhale a further 32 μg.[9][10] The estimated daily exposure from "automobile-related activities" is 49 μg and for driving for one hour is 40 μg.[8]

Smoking: For smokers, cigarette smoking is the main source of exposure to benzene. Estimates are 7900 μg per day (smoking 20 cigarettes per day),[9] 1820 μg/day, and 1800 µg/day.[8]

In 1990, a study reported having found benzene in bottles of Perrier for sale in the United States, resulting in a voluntary product recall.[11][12]

In the early 1990s, the soft drink industry initially approached FDA with concerns about benzene formation in soft drinks. Following testing, FDA asked manufacturers to voluntarily reformulate. By 1993, FDA determined that most drinks had little benzene contamination.[13]

In 1993, research showed how benzene can form from benzoic acid in the presence of vitamin C.[1][14]

In the summer of 1998, a number of well known soft drinks manufacturers had to withdraw large quantities of their products from sale after benzene contamination in some production plants was discovered.[15]

In February 2006, an unnamed former chemist at the FDA publicly revealed that benzene may be created as part of a chemical reaction during production of soft drinks, particularly those having an orange flavor.[18] Full-scale investigations immediately started at the Food Standards Agency (UK) and in Germany to reveal exactly which amounts of benzene, if any, were present, with several other organizations awaiting their findings.[19]

In April 2006, the Korea Food & Drug Administration (KFDA) announced that it had detected benzene in 27 out of 30 (90%) vitamin-enriched drinks on sale in South Korea. It said the detected amount of benzene – ranging from 5.7 to 87.8 ppb – was not harmful to humans but advised manufacturers of beverages containing more than 10 ppb of benzene to voluntarily recall their products.[4]

The FDA released preliminary results[16] in May 2006 for 100 beverages showing that many soft drinks contained low levels of benzene (less than 5 ppb, the federal drinking water limit) while four drinks contained amounts above the standard. Two of these drinks contained amounts 15-18 times above the drinking water standard. Many of the products showed large variations in the amount of benzene they contained. The FDA stated that it is working with manufacturers to reformulate products that contain benzene above the federal drinking water standard.

These test results are both lower and more accurate than a previous long-term study by the FDA. In the Total Diet Study[22] that FDA conducted from 1996 - 2001 to determine the amounts of volatile organic compounds in various foods, FDA used an analytical procedure that caused more benzene to form in the drinks during the test.[23][24]

The FDA emphasized that most beverages contain levels below 5 ppb and pose no risk to consumers. Furthermore, there are no standards for beverages beyond drinking and bottled water. A watchdog organization, the Environmental Working Group, had previously called on the FDA to release its results. The EWG also criticized the FDA for not acting on the Total Diet Study results showing the nearly 80% of the diet soft drinks exceeded the federal drinking water standards.

On 9 June 2006, Health Canada released its study results of benzene levels in beverages. Four products out of 118 had levels above the Canadian guideline of five micrograms per liter for benzene in drinking water (average range 6.0 to 23.0 µg/L). The follow up study the next year found only 3 samples with marginally higher levels and concluded the average levels were quite low.[25][26]

On 24 August 2006, two soft drink manufacturers agreed to settle a class-action lawsuit that had been filed by a group of parents in the Superior Court of the District of Columbia. The two companies, Zone Brands Inc., maker of "BellyWashers" products, and TalkingRain Beverage Co., denied that their products were harmful, but agreed to change the ingredients in their drinks.[27]

Coca-Cola announced that it would be phasing out sodium benzoate from many of its drinks, but not Fanta and Sprite.[28] As of August 2012, Coca Cola Zero and Barq's root beer still contains benzoate (added as potassium salt and sodium salt respectively).[29]

A Belgian study found that plastic packaging may play an important role in the formation of benzene in soft drinks.[30]